Herb Gross explains more about solving systems of linear equations. First, he describes how to change a system that may appear difficult because of the coefficients of the variables into a system that is easier to manipulate using strategies we are familiar with. The idea of using strategies we already know to solve a new kind of problem is demonstrated again in solving a system of 3 linear equations in 3 variables. Have a look at www.adjectivenounmath.com.